Torque tube control device



Aug. 1963 w. BRAUER 3,099,953

TORQUE TUBE CONTROL DEVICE Filed Dec. 21, 1961 INVENTOR. Wa/fer Brauer United States Patent 3,099,953 TORQUE TUBE CUNTROL DEVICE Walter Brauer, P20. Box 727, lngleside, Tex. Filed Dec. 21, 1961, Ser. No. 161,059 7 Claims. (Cl. 100-258) This invention relates to improvements in pressure exerting apparatus for substantially any desired operation on a work piece, and more particularly, but not by way of limitation, to a control device for providing a substantially uniform advance and return for a plurality of spaced ramming pistons utilized for producing pressure on a die or shoe in a work piece forming operation, punching operation, or the like.

There are many operations required on a variety of work pieces wherein pressure is utilized for facilitating the function thereon. For example, a press-brake is in widespread use today for metal bending or forming operations, and pressure is applied to the forming die or press-ram in order that the bending operation may be accomplished. In many other work operations, such as punching, scoring, or otherwise penetrating thereof, it is desirable to utilize pressure against the work piece in order to provide a more eflicient operation. It is common practice to provide a plurality of spaced cylinders having reciprocating pistons carried thereby for transmitting pressure to the die, brake-shoe, or work piece when the operation being performed thereon requires the use of pressure. These cylinder-piston arrangements are frequently of the hydraulic type wherein a fluid is directed to the plurality of cylinders for reciprocating the pistons therein. The cylinders and pistons are normally spaced along the length of the die or shoe in order that the pressure may be applied substantially evenly throughout the working area on the work piece.

Many problems have been encountered in the use of these multiple-cylinder pressure devices. It is difficult to supply the pressure fluid to all of the cylinders at exactly the same time and under exactly the same pressure due to differences in friction because of the varying sizes and lengths of the pressure lines extending to each of the cylinders. This tends to cause the individual pistons to advance and retract unevenly, :or out of synchronization due to the time lag and pressure differentials in the application of the pressure fluid thereagainst. As a result, the pistons may bind or look in the cylinders, and the pressrarn or die contacting the work piece may press unevenly against the work piece, causing an inaccurate or inefficient operation thereon. For example, in the bending of a metallic plate, the bending or pressing action may be improperly initiated at one end instead of uniformly along the entire plate.

This tendency of the uneven movement of the pistons has been only partially overcome or counteracted by the use of various combinations of electrical limit switches, solenoid valves, and complicated piping arrangements for either diverting flow of the pressure fluid to or from the dragging or lagging cylinder, or increasing the pressure to counteract the frictional and flow differences in the cylinders. These devices have not been entirely satisfactory, not only because the problem has not been entirely solved, or eliminated, but also because the switches and additional pipe arrangements are expensive, thus increasing the over-all production costs.

The present invention contemplates a novel torque tube control device for overcoming the tendency of a plurality of ramming pistons, or the like, to advance or retract unevenly. A simple mechanical linkage is estab lished between the cylinders by a torque member, such as a pipe, having a plurality of pulleys or sheaves and counterweights secured thereto. The torque tube is free- Patented Aug. 6, 1963 1y journalled in juxtaposition to the press-brake shoe, or die-bar, or the like, and is fireely rotatable with respect thereto. Counter-weight means are suspended irom the sheaves in one direction, and the sheaves are secured to the die or shoe by a suitable cable whereby the force of the counterweight means is transmitted to the die. If one piston tends to move ahead of the other pistons on either the upstroke or the downstroke, there will be a slightly excessive or increased pressure exerted on the die or press bar adjacent the leading piston. This increased pressure is resisted by the counterweight force whereby the piston will be restrained. Simultaneously, the torque tube may twist slightly due to the pull of the piston on the respective sheave, thereby transmitting this pull to the remaining or additional sheaves secured thereto tor free ing the other pistons, and causing the additional pistons to move with the leading piston. Thus, one cylinder or piston cannot move ahead of the other pistons by any more distance than the slight potential twisting of the torque tube or torque member. In addition, the force of the counterweight means acting against the weight of the ramming device or die-bar substantially reduces the pressure required for the raising or liiting of the ram in the operation of the press apparatus. The novel torque tube control device substantially eliminates any uneven movement of the pistons without the use of expensive valves, electrical connections and pipe arrangements.

It is an important object of this invention to provide a novel device for controlling the advancing and retracting of a multiplicity of ramming pistons, or the like, in such a manner that the pistons remain substantially in synchronization in operation.

It is another object of this invention to provide a novel control device for a pressure application apparatus Wherein a simple mechanical linkage is established between a plurality of ramming pistons for maintaining a substantially uniform application of force for the pressure apparatus.

Another object of this invention is to provide a novel torque tube control device wherein the pressure applied to a die or shoe is counteracted by a. counterweight means for controlling the advancing or retracting of ramming pistons to substantially preclude binding or locking thereof.

A further object or this invention is to provide a. novel torque tube control device wherein the pressure requirements for raising the ramming members is greatly reduced.

A still further object of this invention is to provide a novel torque tube control device for a pressure application apparatus which is simple and eflicient in operation and economical and durable in construction.

Other and further objects and advantageous features of the present invention will hereinafter more fully appear in connection with a detailed description of the drawings in which:

FIGURE 1 is a broken front elevational view of a torque tube control device embodying the invention with a pressure application apparatus depicted in broken lines.

FIGURE 2 is an enlarged sectional view taken .on line 22 of FIGURE 1.

FIGURE 3 is an enlarged front elevational view of one end of the torque tube control device depicted in FIGURE 1.

Referring to the drawings in detail, reference character 10 generally indicates a control device for utilization in conjunction with substantially any apparatus wherein it is desired to apply pressure against a work piece (not shown) for any reason, such as the hydraulic brake press 12 shown in dotted lines in FIGURE 1. The brake press 1'2 comprises the usual work holder or supporting portion 14 having a plurality of spaced cylinders 16 supported thereby, or cooperating therewith. The cylinders 16 are provided with reciprocal pistons 18 which may be actuated by any suitable means (not shown), and are preferably reciprocated within the cylinders 16 by hydraulic pressure, as is well known. The pistons 18 carry a ram member 20, which may be of any suitable type, such as a brake shoe or forming shoe for bending or forming the work piece in accordance with the desired configuration therefor.

The torque tube control device comprises a torque member 22 mounted in juxtaposition to the press apparatus 12, as clearly shown in FIGURE 1. The torque member 22 may be constructed from any suitable tubular or cylindrical material, such as heavy walled pipe, or the like, and is journalled at the opposed ends in suitable bearing members 24 and 26 for free rotation with respect to the apparatus 12. The bearings 24 and 26 may be disposed in the rear portion of the frame (not shown) of the apparatus 12, or may be supported in a separate housing or support structure (not shown), as desired, for retaining the torque tube 22 in spaced relationship with the ram member 20, and preferably substantially parallel thereto.

A plurality of relatively small longitudinally spaced pulleys or sheaves 28 are rigidly secured to the tube 22 in any suitable manner, such as keyed thereto, or welded, or the like. Substantially any number of the pulleys 28 may be provided along the length of the tube 22, and as shown herein two of the pulleys 28 are utilized and secured in the proximity of each end of the tube 22. If the distance of travel of the ram 20 is relatively short, it may be desirable that the sheaves 28 be of a half-sheave or semi-circular configuration, as depicted herein. Of course, the size and configuration of the sheaves 28 may be varied depending upon the working forces and conditions required for the apparatus 12. A second sheave or pulley 30 is similarly rigidly secured to the tube 22 adjacent each of the sheaves 28, and may be of any suitable diametrical size. As'shown in FIGURE 2, it may be preferable that the sheave 30 be of a relatively larger diameter than the respective sheave 28 in order to multiply the effect of the operation thereof whereby a lesser weight may be utilized therewith, as will be hereinafter set forth. The sheaves 30 depicted herein are of a similar configuration to the sheaves 28, but it is to be understood that the general configuration of the sheaves 30 may be as desired in accordance with the working operations of the apparatus 12.

A cable or line 32 extends over each of the smaller sheaves 28 for connection at 34 with the ram member 20. 'Of course, a rotatable idler sheave 36 (FIGURE 2) may be provided for each of the sheaves 28 and interposed 'or journalled between the sheaves 28 and ram 20 by a support bracket 37 for receiving the cable 32 therearound in order to facilitate the supporting of the cable 32, as is well known. The opposite end of each cable 32 is secured to a suitable threaded adjusting rod 38 in any well known manner. A nut 40 is threadedly secured on the rod 38 and bears against a sleeve 42 which is secured to the pulley 30 adjacent the pulley 28 in such a manner that rotation of the nut 40 will move the rod 38 longitudinally or reciprocally therein whereby the length of the cable '32 extending between the pulley 28 and the ram 20 may be adjusted. In this manner, each cable 32 may be adjusted to provide a substantially level or horizontal position for the ram 20.

A second cable or line 44 is secured to the pulley 30 in any suitable manner, such as by the anchor member 46 and extends over the pulley 30 for connection with a counterweight member 48 (FIGURE 1). As hereinbefore set forth, the utilization of the two sizes of pulleys 28 and 30 as shown herein multiplies the effect of the counterweight, thus reducing the size or weight required therefor. .In addition, the length of the cable 44 between the sheave 30 and counterweight 48 may be relatively short whereby the counterweight is suspended rearwardly of the ram 20, and spaced above the ground or floor level. It is preferable that the size efifect of the counterweights be particularly selected to be slightly less than the weight of the die-holder bar or ram 20 and the pistons 18. This is found to facilitate the reciprocal movement of the pistons 18 while maintaining a slight pressure in the cylinders 16 to properly seat the piston packing (not shown) against the cylinder walls.

As hereinbefore set forth, substantially any number of the cylinders 16 and complementary pistons 18 may be provided for the press apparatus 12, and it may be desirable to provide a pulley 28 and sheave 30 in the proximity of each piston 18. However, as shown herein, two of the pulley 28 and sheave 30 combinations are provided with one at each end of the torque tube 22 and in the proximity of the outermost pistons 18. It will be apparent that the force of the counterweights 48 is transmitted to the ram member 20 through the cooperating sheaves 30 and 28 and cables 44 and 32 whereby the counterweights 48 constantly exert an upward force on the ram 20. However, the force of the counterweights 48 is less than the combined weights of ram 20 and pistons 18, thus assuring there will be no interference with the normal operation of the apparatus 12.

Operation The torque tube control device may be installed in juxtaposition with substantially any desired work apparatus wherein it is required to use force or pressure to perform an operation on a work piece. As depicted herein, the apparatus 12 is a press brake wherein the ram or die holder 20 is lowered and raised by the advance or retractmovement of the pistons 18. The pistons 18 are reciprocated within the cylinders 16 by hydraulic pressure, as is well known.

On either the upstroke or the downstroke of the pistons 18 for raising or lowering the raw member 20, as the pistons 18 move within the respective cylinders 16, if any of the pistons has less drag, or receives more pressure from the hydraulic fluid, it will try to move ahead of the other pistons. This leading piston will thus push harder against the die-bar or ram 20. When the ram section or portion under the piston, or closely disposed thereto tries to move in response to the increased force from the leading piston, the ram'will pull against the cable 32 most closely disposed thereto. The force in the cable 32 pulls over the pulley 28 and acts on the pulley 30 to try to pick up the weight of the counterweight 48 associated therewith. Of course, the drag effect on the leading piston is considerably less than the weight of the counterweight 48, and thus the piston is restrained from moving ahead of the other pistons.

Simultaneously, the torque tube member 22 will try to twist slightly due to the pull of the free cylinder, or leading piston, and this pull is transmitted to the additional pulley combinations by the tube 22 for freeing the other pistons by overcoming the drag or friction, thus causing the other pistons to move with the free cylinder. The torque tube and pulley combination provides a simple mechanical linkage between the cylinders whereby one cylinder or piston cannotget ahead of the other pistons by any more distance than the slight potential twisting of the torque-pipe or tube member 22.

Of course, this arrangement can be applied to two cylinders, or substantially any number of cylinders with as many pulley and counterweight arrangements as deemed necessary for the space and weight requirements of the particular apparatus 12 with which the control device 10 is to be used. The novel torque tube control device 10 may be readily installed with substantially any existing machine or pressure application apparatus without alternation of the normal operation thereof. The torque tube 22 can be readily attached or secured to the rear of the frame of the apparatus by securing the bearing members 24 and 26 thereto for journalling the tube 22 in juxtaposition to the apparatus 12. As hereinbefore set forth, the counterweights 48 constantly exert an upward pressure or force on the die-bar or ram member 20, thus greatly reducing the force necessary for raising or lifting the ram. Thus, since gravity facilitates the downward movement of the ram, and the counterweights facilitate the upward movement thereof, the entire force required for operation of the apparatus 12 is greatly reduced.

From the foregoing, it will be apparent that the present invention provides a novel control device for assuring a substantially synchronized movement of a plurality of cylinders or pistons against the ram member or die-bar of substantially any apparatus for applying pressure to a work piece. The novel torque tube control device may be readily installed with the forming apparatus without interfering in any manner with the normal operation thereof, and greatly reduces the force requirements for actuation of the pressing member. Any tendency for the pistons to reciprocate at uneven speeds or pressures is easily overcome by the pulley-counterweight arrangement. A simple mechanical linkage is established between the plurality of cylinders for maintaining the pistons in an aligned action during the reciprocation thereof. The novel device is simple and efficient in operation and economical and durable in construction.

Whereas, the present invention has been described in particular relation to the drawings attached hereto, it should be understood that other and further modifications, apart from those shown or suggested herein, may be made within the spirit and scope of this invention.

What is claimed is:

1. In combination with a vertically reciprocal pressure exerting apparatus, a control device comprising torque means secured in juxtaposition to the pressure exerting apparatus, said pressure exerting apparatus being elongated and having means spaced therealong for reciprocation thereof, means connecting the torque means with the pressure exerting apparatus for transmitting slight twisting to the torque means, and counterweight means carried by the torque means so arranged to tend to pull the pressure exerting apparatus upwardly and for cooperating with the twist transmitting means and torque means to maintain a substantially even force for the pressure exerting apparatus throughout the operation thereof.

2. In combination with an elongated pressure exerting apparatus having a plurality of vertically reciprocal pistons spaced longitudinally therealong, a control device comprising torque means connected with the pressure exerting apparatus, said torque means having means for transmitting a slight twisting thereto whereby a simple mechanical linkage is established between the pistons, counterweight means carried by the torque means and tending to pull the pressure exerting apparatus upwardly, said mechanical linkage responsive to unequal pressure from the pistons for maintaining the actuation of the pistons in substantial synchronization during reciprocation thereof for equalizing the pressure force of the pressure exerting apparatus during the operation thereof.

3. In combination with a pressure exerting apparatus having a plurality of pistons for vertically reciprocating a pressure bar, a control device comprising a torque tube secured in juxtaposition to the pressure bar and journalled for rotation, at least two spaced pulley means secured to the torque tube, means interconnecting the pulley means and the pressure bar, counterweight means carried by the pulley means and acting against the weight of the pressure bar, said pulley means responsive to a pressure differential on the pressure bar from any one of the pistons through slight twisting of the torque tube for transmitting the motion of the said one piston to the remaining pistons for substantially equalizing the action of all the pistons whereby a substantially even force is maintained for the pressure bar during operation of the pressure exerting apparatus.

4. 'In combination with a pressure exerting apparatus having a plurality of pistons for vertically reciprocating a pressure member, a control device comprising a torque tube rotatably journalled in juxtaposition to the pressure member, a plurality of longitudinally spaced sheaves rigidly secured to the torque tube, means connecting the sheaves with the pressure member, counterweight means carried by the sheaves and acting against the weight of the pressure member, said sheaves responsive to any leading movement of one of the pistons for transmitting the motion to the remaining pistons by a slight twisting of the torque tube for maintaining a substantially leven force for the pressure member during operation of the pressure apparatus.

5. A torque tube control device for a brake press having a plurality of pistons for vertically reciprocating an elongated press bar and the pistons being longitudinally spaced along the length of the press bar, and comprising a torque tube rotatably journalled in juxtaposition to the press bar, a plurality of first spaced sheaves rigidly secured to the torque tube, a plurality of second spaced sheaves rigidly secured to the torque tube, counterweight means, and means cooperating between the sheaves for connecting the counterweight means with the press bar, said sheaves and counterweight means cooperating upon uneven movement of the pistons for transmitting a slight twist to the torque tube for substantially synchronizing the movement between the pistons to maintain an even force for the press bar during operation of the brake press, and said counterweight means also facilitating elevating of the press bar during operation of the brake press.

*6. A torque tube control device for a press apparatus having a plurality of pistons for vertically reciprocating an elongated press member and the pistons being spaced along the length of the press member, and comprising a torque tube rotatably journalled in juxtaposition to the press member, a plurality of spaced first sheave members secured to the torque tube, means connecting the first sheave members to the press member, a second sheave member secured to the torque tube in the proximity of each of the first sheave members, counterweight means carried by the second sheave members, means interconnecting the first and second sheave members whereby the weight of the counterweight means acts against the weight of the press member, and said sheaves and counterweight means cooperating with the torque tube for transmitting slight twisting thereto to provide a mechanical link-age between the plurality of pistons for maintaining a substantially synchronized movement therebetween to provide an even force for the press member during operation of the press apparatus, and said counterweight means facilitating elevating of the press member during operation of the press apparatus.

7 A torque tube control device for a press apparatus having a plurality of pistons for vertically reciprocating an elongated press member and the pistons being spaced throughout the length of the press member, and compnsmg a torque tube rotatably journalled in juxtaposition to the press member, a plurality of spaced first sheave members secured to the torque tube, means connecting the first sheave members to the press member, means cooperating with the connecting means for adjusting the level of the press member, a second sheave member rigidly secured to the torque tube in the proximity of each of the first sheave members and connected thereto by the ad usting means, counterweight means carried by the second sheave members for acting against the Weight of the press member, and said sheaves and counterweight means transmitting slight twisting to the torque tube to provide a mechanical linkage between the plurality of pistons for maintaining a substantially even force on the press memher during operation of the press apparatus, and said a .8 counterweight means facilitating raising of the press mem- 1,307,764 Sullivan June 24, 1919 her during operation of the press apparatus. 1,467,201 Shriver Sept. 4, 1923 1,469,689 Prius Oct. 2, 1923 References Cited in the file of this patent 5 I OTHER REFERENCES UNITED STATES PATENTS 1 German printed application, N68141 b/SSa, Oct. 18,

955,852 Coyle Apr. 26, 1910 1956, 

1. IN COMBINATION WITH A VERTICALLY RECIPROCAL PRESSURE EXERTING APPARATUS, A CONTROL DEVICE COMPRISING TORQUE MEANS SECURED IN JUXTAPOSITION TO THE PRESSURE EXERTING APPARATUS, SAID PRESSURE EXERTING APPARATUS BEING ELON-; GATED AND HAVING MEANS SPACED THEREALONG FOR RECIPROCATION THEREOF, MEANS CONNECTING THE TORQUE MEANS WITH THE PRESSURE EXERTING APPARATUS FOR TRANSMITTING SLIGHT TWISTING TO THE TORQUE MEANS, AND COUNTERWEIGHT MEANS CARRIED BY THE TORQUE MEANS SO ARRANGED TO TEND TO PULL THE PRESSURE EXERTING APPARATUS UPWARDLY AND FOR COOPERATING WITH THE TWIST TRANSMITTING MEANS AND TORQUE MEANS TO MAINTAIN A SUBSTANTIALLY EVEN FORCE FOR THE PRESSURE EXERTING APPARATUS THROUGHOUT THE OPERATION THEREOF. 